On Thu, Apr 19, 2018 at 01:30:32PM +0200, Maarten Lankhorst wrote: > Op 19-04-18 om 13:22 schreef Ville Syrjälä: > > On Thu, Apr 19, 2018 at 02:36:42AM +0000, Srinivas, Vidya wrote: > >> > >> > >> > >>> -----Original Message----- > >>> From: Ville Syrjälä [mailto:ville.syrjala@xxxxxxxxxxxxxxx] > >>> Sent: Thursday, April 19, 2018 12:06 AM > >>> To: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx> > >>> Cc: Srinivas, Vidya <vidya.srinivas@xxxxxxxxx>; intel- > >>> gfx@xxxxxxxxxxxxxxxxxxxxx > >>> Subject: Re: [PATCH v4 6/6] drm/i915: Add > >>> skl_check_nv12_surface for NV12 > >>> On Wed, Apr 18, 2018 at 08:06:57PM +0200, Maarten Lankhorst wrote: > >>>> Op 18-04-18 om 17:32 schreef Ville Syrjälä: > >>>>> On Wed, Apr 18, 2018 at 09:38:13AM +0530, Vidya Srinivas wrote: > >>>>>> From: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx<mailto:maarten.lankhorst@xxxxxxxxxxxxxxx>> > >>>>>> We skip src trunction/adjustments for > >>>>>> NV12 case and handle the sizes directly. > >>>>>> Without this, pipe fifo underruns are seen on APL/KBL. > >>>>>> v2: For NV12, making the src coordinates multiplier of 4 > >>>>>> v3: Moving all the src coords handling code for NV12 to > >>>>>> skl_check_nv12_surface > >>>>>> Signed-off-by: Maarten Lankhorst > >>>>>> <maarten.lankhorst@xxxxxxxxxxxxxxx<mailto:maarten.lankhorst@xxxxxxxxxxxxxxx>> > >>>>>> Signed-off-by: Vidya Srinivas <vidya.srinivas@xxxxxxxxx<mailto:vidya.srinivas@xxxxxxxxx>> > >>>>>> --- > >>>>>> drivers/gpu/drm/i915/intel_display.c | 39 > >>>>>> ++++++++++++++++++++++++++++++++++++ > >>>>>> drivers/gpu/drm/i915/intel_sprite.c | 15 ++++++++++---- > >>>>>> 2 files changed, 50 insertions(+), 4 deletions(-) > >>>>>> diff --git a/drivers/gpu/drm/i915/intel_display.c > >>>>>> b/drivers/gpu/drm/i915/intel_display.c > >>>>>> index 925402e..b8dbaca 100644 > >>>>>> --- a/drivers/gpu/drm/i915/intel_display.c > >>>>>> +++ b/drivers/gpu/drm/i915/intel_display.c > >>>>>> @@ -3118,6 +3118,42 @@ static int skl_check_main_surface(const > >>> struct intel_crtc_state *crtc_state, > >>>>>> return 0; > >>>>>> } > >>>>>> +static int > >>>>>> +skl_check_nv12_surface(const struct intel_crtc_state *crtc_state, > >>>>>> + struct intel_plane_state *plane_state) { > >>>>>> + int crtc_x2 = plane_state->base.crtc_x + plane_state->base.crtc_w; > >>>>>> + int crtc_y2 = plane_state->base.crtc_y + > >>>>>> +plane_state->base.crtc_h; > >>>>>> + > >>>>>> + if (((plane_state->base.src_x >> 16) % 4) != 0 || > >>>>>> + ((plane_state->base.src_y >> 16) % 4) != 0 || > >>>>>> + ((plane_state->base.src_w >> 16) % 4) != 0 || > >>>>>> + ((plane_state->base.src_h >> 16) % 4) != 0) { > >>>>>> + DRM_DEBUG_KMS("src coords must be multiple of 4 for > >>> NV12\n"); > >>>>>> + return -EINVAL; > >>>>>> + } > >>>>> I don't really see why we should check these. The clipped > >>>>> coordinates are what matters. > >>>> To propagate our limits to the userspace. I think we should do it for > >>>> all formats, but NV12 is the first YUV format we have tests for. If we > >>>> could we should do something similar for the other YUV formats, but they > >>> have different requirements. > >>>> In case of NV12 we don't have existing userspace, there will be > >>>> nothing that breaks if we enforce limits from the start. > >>> But what about sub-pixel coordinates? You're totally ignoring them here. > >>> We need to come up with some proper rules for this stuff. > >>>>>> + > >>>>>> + /* Clipping would cause a 1-3 pixel gap at the edge of the screen? */ > >>>>>> + if ((crtc_x2 > crtc_state->pipe_src_w && crtc_state->pipe_src_w % > >>> 4) || > >>>>>> + (crtc_y2 > crtc_state->pipe_src_h && crtc_state->pipe_src_h % 4)) > >>> { > >>>>>> + DRM_DEBUG_KMS("It's not possible to clip %u,%u to > >>> %u,%u\n", > >>>>>> + crtc_x2, crtc_y2, > >>>>>> + crtc_state->pipe_src_w, crtc_state->pipe_src_h); > >>>>>> + return -EINVAL; > >>>>>> + } > >>>>> Why should we care? The current code already plays it fast and loose > >>>>> and allows the dst rectangle to shrink to accomodate the hw limits. > >>>>> If we want to change that we should change it universally. > >>>> Unfortunately for the other formats we already have an existing > >>>> userspace > >>>> (X.org) that doesn't perform any validation. We can't change it for > >>>> that, but we can prevent future mistakes. > >>> We should do it uniformly. Not per-format. That will make the code > >>> unmaintainable real quick. > >>>>>> + > >>>>>> + plane_state->base.src.x1 = > >>>>>> + DIV_ROUND_CLOSEST(plane_state->base.src.x1, 1 << 18) << > >>> 18; > >>>>>> + plane_state->base.src.x2 = > >>>>>> + DIV_ROUND_CLOSEST(plane_state->base.src.x2, 1 << 18) << > >>> 18; > >>>>>> + plane_state->base.src.y1 = > >>>>>> + DIV_ROUND_CLOSEST(plane_state->base.src.y1, 1 << 18) << > >>> 18; > >>>>>> + plane_state->base.src.y2 = > >>>>>> + DIV_ROUND_CLOSEST(plane_state->base.src.y2, 1 << 18) << > >>> 18; > >>>>> Since this can now increase the size of the source rectangle our > >>>>> scaling factor checks are no longer 100% valid. We might end up with > >>>>> a scaling factor that is too high. > >>>>> I don't really like any of these "let's make NV12 behave special" > >>>>> tricks. We should make the code behave the same way for all pixel > >>>>> formats instead of adding format specific hacks. > >>>> This is not nivalid because we restrict the original src coordinates > >>>> to be a multiple of 4, you can only clip to something smaller, not to > >>>> something bigger. :) > >>> The clipped coordinates can be whatever thanks to scaling/etc. > >>> Also why are we trying to make everything a multiple of four? I don't > >>> remember any hw restrictions like that. > >> > >> > >> Hi > >> > >> > >> As per WA1106, Display corruption/color shift observed when using NV12 with 270 rotation or 90 rotation + horizontal flip. > >> > >> WA: NV12 with 270 rotation or 90 rotation + horizontal flip requires the programmed plane height to be a multiple of 4. > > Does plane height here mean src height or dst height? > > > > Either way I don't see why we aren't just checking for the right thing > > instead of trying to mandate a four pixel alignment everywhere. > > > Agreed, what about the below diff, would this be acceptable to you? I deliberately ignore the last 16 bits as that is what we currently do anyway for all formats. > > diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c > index 4b3735720fee..3ff7b5491446 100644 > --- a/drivers/gpu/drm/i915/intel_display.c > +++ b/drivers/gpu/drm/i915/intel_display.c > @@ -3090,6 +3090,31 @@ static int skl_check_main_surface(const struct intel_crtc_state *crtc_state, > return 0; > } > > +static int > +skl_check_nv12_surface(const struct intel_crtc_state *crtc_state, > + struct intel_plane_state *plane_state) > +{ > + /* Display WA #1106 */ > + if (plane_state->base.rotation != (DRM_MODE_REFLECT_X | DRM_MODE_ROTATE_90) && > + plane_state->base.rotation != DRM_MODE_ROTATE_270) > + return 0; Hmm. I wonder if that's what the spec actually means. The HSDs only talk about 270 degree rotation. So I guess this interpretation could be correct. > + > + /* Because x/y are src coordinates will be rotated, we look at x/width here. */ > + if (((plane_state->base.src_x >> 16) % 4) != 0 || > + ((plane_state->base.src_w >> 16) % 4) != 0) { > + DRM_DEBUG_KMS("src x/w must be multiple of 4 for rotated NV12\n"); > + return -EINVAL; > + } > + > + /* And round y here */ > + plane_state->base.src.y1 = > + DIV_ROUND_CLOSEST(plane_state->base.src.y1, 1 << 18) << 18; > + plane_state->base.src.y2 = > + DIV_ROUND_CLOSEST(plane_state->base.src.y2, 1 << 18) << 18; Why not just a simple if (drm_rect_height(src) >> 16 % 4 != 0) return -EINVAL; ? > + > + return 0; > +} > + > static int skl_check_nv12_aux_surface(struct intel_plane_state *plane_state) > { > const struct drm_framebuffer *fb = plane_state->base.fb; > @@ -3173,6 +3198,9 @@ int skl_check_plane_surface(const struct intel_crtc_state *crtc_state, > * the main surface setup depends on it. > */ > if (fb->format->format == DRM_FORMAT_NV12) { > + ret = skl_check_nv12_surface(crtc_state, plane_state); > + if (ret) > + return ret; > ret = skl_check_nv12_aux_surface(plane_state); > if (ret) > return ret; -- Ville Syrjälä Intel _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
